A contribution to the assessment of scenic quality of landscapes based on preferences expressed by the public

The purpose of this paper is to validate a model for predicting the public's preference for a landscape using simple statistical techniques. The model assigns numerical values to 42 landscape variables grouped into physical, aesthetic and psychological attributes. The landscape value is obtained using an additive value function. The results of the model on certain landscapes are compared with the preference expressed by the public in a survey of 183 people.The homogeneity of the survey responses was checked in each photograph. It was determined that means and standard deviations of the scores represent the true preference.A strong positive association was observed between preference and certain landscape attributes such as expression, soil use or colour. A marked negative association was detected with respect to landscape alterations.A linear regression was carried out to analyse the predictive capacity of the model. The independent variable was the global score assigned by the model to each photograph and the dependant variable was the mean of the scores assigned by the survey respondents. The high level of correlation obtained indicates that the model is a good predictor of the public's preferences in relation to the set of photographs shown in the survey.To complete the analysis of the model as a preference predictor, a multiple linear regression was carried out between the mean score obtained in the survey and the model elements. Attributes and variables that have the greatest influence on pubic preference were detected.     

An integrated approach for ex-ante evaluation of public policies for sustainable agriculture at landscape level

An integrated methodological framework for ex-ante evaluation and planning of public policies for sustainable agriculture at agro-landscape level is proposed. The components of the framework are to: (1) determine the private, i.e. farmers’, and public benefits associated to agro-landscapes, consisting of an agricultural land-use system, according to its performance for several market and non-market functions. Market forces determine the market benefits and preferences of society the non-market benefits; (2) explore and select potential sustainable agro-landscapes based on the private and public benefits associated with possible land-use alternatives; (3) define efficient public policy mechanisms for improving social net benefit of agro-landscapes.The framework is illustrated with a case study in a small dairy farming dominated agro-landscape in The Netherlands, with gross margin, landscape quality, nature value and environmental health as the analysed ecosystem functions. Alternative landscapes consisting of hedgerow configurations and grassland management practices were explored, yielding a set of alternatives representing the solution space in terms of change in private and public benefits. Policy mechanisms were defined to move from the current to a desired landscape based on changes in social net benefits. Moreover, the necessity of a modification in the current agri-environmental support was analysed for each landscape. The analysis considered all farmers in the agro-landscape jointly. The results for the case study showed potential prototypes of landscapes and their performance compared to the current landscape. Extension was the most efficient policy mechanism to promote the change to the socially optimum landscape alternative.     

工程建设占地指标市场化研究

研究目的：确定缓解有限的土地资源与不断增长的工程建设用地需求之间矛盾的方法。研究方法：文献分析法、判断分析法。研究结果：设立区域乃至全国性的土地占用指标交易市场体系,规划许可范围内的工程建设项目在该市场上可以购买占地指标,所得资金专款专用于土地整理复垦工作,通过该市场将整个国土内的“占”和“补”联系起来,实现耕地占补的“项目平衡”,最终实现宏观意义上的耕地 “占补平衡”。     

基于多维尺度分析的土地科学决策支持系统研究现状分析

研究目的：分析国内近16年土地科学决策支持系统研究动态,探讨其发展趋势。研究方法：共词聚类分析法和多维尺度分析法。研究结果：通过分析土地科学决策支持系统的相关文献,土地科学决策支持系统可分为土地利用规划决策支持系统、土地空间决策支持系统、土地评价决策支持系统、土地生态安全决策支持系统以及其他土地管理决策支持系统5种类型,并对其研究现状和发展趋势进行了分析。研究结论：（1）土地利用规划决策支持系统目前国内研究较多,关注度较高。其他方向还有待进一步研究。（2）随着3S、专家系统、数据挖掘等技术的不断发展,决策支持系统得到不断的完善和发展,一些新的技术和理论方法将被引入决策支持系统。土地科学决策支持系统将向集成化、智能化、网络化及可视化方向发展。     

土地利用总体规划修编指标利益冲突问题研究

研究目的：分析规划修编中,中央和地方、地方和地方之间在确定规划指标时利益冲突的成因和表现形式。研究方法：文献资料法,博弈分析法。研究结果：中央政府和地方政府土地利用追求目标上的差异是导致规划指标分解过程中产生冲突的主要原因。政府之间信息不对称是造成指标分解冲突的重要原因。研究结论：整合中央和地方的利益、实行参与式规划,做好规划修编过程中的上下结合,减少冲突,使得各项指标的确定能够有利于协调区域发展,并得到各地区的认同。     

建设用地扩张对经济增长的贡献及其区域差异研究

研究目的：应用1999 — 2007年分省数据,测度近年建设用地扩张对中国及不同区域经济增长的贡献及变化趋势,为土地政策制定提供依据。研究方法：效率评价法、多元回归分析法、比较分析法。研究结果：（1）1999 — 2007年中国固定资本、劳动力和建设用地的产出弹性分别为0.745、0.274和0.083;（2）初级产品阶段地区、工业化阶段地区、发达经济阶段地区建设用地的产出弹性分别为0.376、0.068和0.066;（3）地区技术效率和土地宏观调控对建设用地扩张存在显著抑制作用。研究结论：（1）建设用地扩张对经济增长的贡献随着发展阶段演进逐渐减小;（2）对处于不同发展阶段的地区,应实行差别化的土地管理策略与绩效考核方法。     

林地资源与农户林业收入的分析

首先对林地资源与林业收入的关系进行理论分析,然后运用福建省顺昌县农户林业收入的调查数据,分别对农户林地资源的数量、林地资源的经营类型与林业收入的关系进行实证分析。研究结果表明:林地资源是农户参与林业收入分配的重要形式;农户林地资源数量越多,其家庭林业收入也越高;农户林地资源的经营类型不同,其家庭林业收入也不同;竹林经营和经济林经营对目前农户林业收入的增加具有显著的影响。     

中国木质林产品国际竞争力的实证分析

选取15个主要木质林产品大国(地区)2003～2007年的数据,运用国际市场占有率、贸易竞争指数、显示性比较优势指数、出口增长优势指数、出口依存度、出口贡献率、净出口7个国际竞争力评价指标,采用主成分分析法对木质林产品的国际竞争力进行比较分析,得出结论:中国排在加拿大、印尼、马来西亚、俄罗斯、德国之后;中国木质林产品对外贸易规模不断增加,在世界木质林产品贸易中的地位越来越重要。同时,提出提升竞争力的对策。     

Stochastic efficiency analysis with risk aversion bounds: a correction

A recent paper by Hardaker et al. (The Australian Journal of Agricultural and Resource Economics, 48, 2004a, 253) and book by Hardaker et al. (Coping with Risk in Agriculture, 2004b) describe a procedure for determining an efficient set from among a set of random alternatives. This procedure, called stochastic efficiency with respect to a function (SERF), is claimed to make the same assumption concerning the risk aversion measures as does stochastic dominance with respect to a function (SDRF). This is claim is incorrect. SERF imposes an additional requirement on the risk aversion measures of the decision makers. Both procedures assume a lower and an upper bound on risk aversion, but SERF also assumes that all risk aversion measures are of the same functional form as these lower and upper bound functions. This additional strong requirement on risk preferences implies that the efficient set identified under SERF is usually smaller than that identified using SDRF.     

改革开放30年中国集体林发展趋势分析

通过集体林区改革开放以来各项政策、制度的变化,对森林资源、木材及木质产品供给、造林面积、营林投资、林业重点工程、林地生产力与利用率、农民收入、环境质量与经营发展之间的关系等多方面的绩效分析,指出:集体林区已经取代了东北国有林区,成为我国重要的木材及木质产品基地;但集体林区营林投资呈下降态势;林地生产力和林地利用率虽然提高,但仍处于较低水平;农民是林业生产的主体,但在林业生产中并没有得到较大的好处,在农户家庭收入中所占比重很低。研究表明,林业家庭经营形式并不十分适合中国集体林区,在一定程度上制约了集体林区的发展,尚需与时俱进地开展集体林产权制度改革,在产权清晰基础上,引导适度林地流转,促进规模经营,鼓励专业化经营。同时要对产品与服务市场、林业税费制度、采伐制度、生态效益补偿制度等协调配套改革,把集体林产权制度改革纳入到解决"三农"问题的大背景中加以解决。最后指出,产权的明确与清晰是集体林业发展的前提和必要条件,而不是全部。激励和竞争同样极其重要,建立相应的激励机制是保证我国集体林发展的充分条件。